package com.jzoffer2;

import java.util.Scanner;

/**
 * TODO
 *
 * @author lefly
 * @version 1.0
 * @classname No10_2
 * @description
 * @date 2021/1/30 下午5:57
 */
public class No10_2 {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        int res = numWays(n);
        System.out.println(res);
    }

    public static int numWays(int n) {
        int a = 1, b = 1, sum;
        for(int i = 0; i < n; i++){
            sum = (a + b) % 1000000007;
            a = b;
            b = sum;
        }
        return a;

    }

}
